Yes, Orion speakers thump. <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'> If you're looking for component speakers, the Cobalt series are #### good. I installed those in my car a month or so back, and they hit hard enough just running off the 45 watt deck output to make my rear view mirror useless. And the sound quality and clarity is just as good. They're big speakers, though, so you'll have to do a bit of custom mounting in the doors most likely (at least I did on my S14).
The same thing applies to Orion subs, though I would get XTR Pro's if you're looking to conserve space. They're designed to operate in small enclosures, and the Orion website even has custom box designs you might consider.
Obviously I'm biased towards Orion, but here's the deal... You will be hard pressed to find speakers that outdo the Cobalt series, which is the lowest level of speaker Orion makes. As you go up in speaker quality, the things you can make your car system do are amazing. The one drawback is that Orion is expensive and hard to find, as they only allow select people to deal in their items. If you're even considering Orion, you can find the nearest location to you on the locator thingy on their site, and go talk to one of the people there.
Their site is
http://www.orioncaraudio.com